Molding mechanism



y 4, 1938.. c. w. G'QQDWIN 2,118,080

MOLDING MECHANISM Original Filed June 24, 1933 2 Sheets-Sheet l y 1938.c. w. GOODWIN 2,118,080

MOLDING MECHANI SM Original Filed June 24, 1953 2 Sheets-Sheet 2Patented May 24, 1938 MOLDING MECHANISM Carl W. Goodwin, Plainfield, N.J., ,assignor to American Seal-Kan Corporation of Delaware, Wilmington,Del a corporation of Delaware Original application June 24, 1933, SerialNo.

677,483. Divided and this application Decem-. ber 11, 1935, Serial No.53,897

4 Claims.

This invention relates to mechanism for forming up articles from sheetmaterial and more particularly from paper which has been so pretreatedthat it can be successfully subjected to molding and pressingoperations. A purpose of this invention is to form up or mold such sheetmaterial into such form that the article produced may be used as a coverfor a lipped receptacle so that the cover may be snapped on or off, andwhen on will hold the contents of the receptacle securely even when thereceptacle is inverted. To this end, the cover is formed up with amarginal flange provided with an inwardly extending marginal bead ofsuch a uniform, dense structure, and without apparent folds, that itwill not be permanently deformed during use. This application is adivision of my application Serial No. 677,483, for Paper article andmethod of forming it, filed June 24, 1933.

For a more complete understanding of this invention reference may be hadto the accompanying drawings, in which,

Figure 1 is a central vertical section through the cap-forming portionsof the forming dies.

Figure 2 is a horizontal section on line 22 of Figure 1.

Figure 3 is a fragmentary view partly broken away showing the capapplied to the top of a paper cup.

Figure 4 is a View similar to Figure 3, but showing the cap applied to atumbler or glass.

Figures 5 to 8 inclusive are detail sections showing successive stagesof the cap-forming operation.

Referring first to Figures 1, 2 and 3, at I and 2 are indicatedcooperating dies. The lower die 2 comprises a socket member 3 in whichis positioned a yielding base member 4 which may be depressed againstthe pressure of a spring 5 to the base of the socket with its upper face6 substantially flush with the lower edge of a counterbored portion 7 atthe upper end of the socket 3. At 8 is shown a plate member having anopening 9 therein flared at Hi, this plate member being movable topresent in succession disks of paper to be formed between the dies and2. The disk of paper when presented lies within the flaring portion Inof this plate 8 and is forced downwardly therethrough by the plunger 20of the die I and onto the base 5. This plunger 20 is provided withsegmental portions 2i and 22, which, as shown best in Figure 2, arearranged in two sets having mating inclined faces 23. These faces 23 areinclined to the directions of motion of the pieces in collapsing andexpanding, the

condition also the portions 22 are still further retracted into thepositions shown in Figurer2. The portions 22, however, have inclinedinner upper faces 26 with which cooperate a frustroconical portion 21 ofan expanding block 28,,so

that as the block 28 is pushed downwardly relative to the members 2| and22, both these sets of members are forced outwardly, the members 22being moved out relative to the members 2| until their outer faces formwith the outer faces of the portion 2| a continuous circumference. Boththe members 2| and 22 are provided with segmental portions of an annularrib 3|), which, when these segments are expanded, form together acontinuous rib about the lower end of the plunger 20. i V

The firstportion of the motion of the plunger 20 into the socket 3,carrying the central portion of the paper disk therewith, causes themarginal portion of the paper disk to be bent upwardly as shown at 40 inFigure 5, the central portion 4! of the disk being seated upon the base6, the segmental portions 2| and 22 being then in expanded'condition sothat the flange 49 is engaged between the socket wall and the rib 3!)adjacent to the face of the disk. When the plunger has entered thesocket sufiiciently far to seat the base member 4 against the base ofthe socket 3 into the position shown in Figure 6, the outer portion ofthe disk 4|] just inwardly of the flange is seated on the base of thecounterbored portion 1, and an annular forming member 42 provided with aconcave lower face 43 has engaged the upper edge of the flange 4i! andhas upset and pressed it down endwise somewhat into the space 44 abovethe rib 36 and between the segments 2| l and 22 and the wall of thesocket 3, this space being substantially wider than the thickness of thepaper stock, as is shown in Figures 5 and 6.

Engagement of the member 42 on the upper edge flange produces anupsetting action on the 4 material without substantial folding orrolling of.

the sheet material on itself so that when the member 42 is in itsextreme downward position,

as shown in Figure 8, this fibrous stock has been 7 upset and compactedon itself to form a homogeneous, highly compacted felted fibrous masswithout seam or fold and ;molded into a bead co figuration projectinginwardly from the outer wall of the flange. On raising the die member[from the die member 2, the die parts are returned to their originalposition and'the formed" cap is removed from the socket. 3, while thesprings 25 act to retract the segmental portions, thus freeing theformed cap from the die member I.

In order to condition the paper stock so that it is capable of beingupset and molded around its marginal flange and likewise to render itwater-resistant or waterproof, it is desirable to pro-treat it withmoisture and a water-resisting compound such as wax. The treatment actsto temper the fibers and facilitates the molding operation and thecompacting of the fibers together. Preferably along with the paraffin isincluded a small percentage of a hardening wax such as carnauba orMontan wax.

Such a cap when formed may be snapped onto the top of a paper cup, suchas shown in Figure 3, provided with amarginal head 50 at its upper edge,the molded bead portion 45 of the cap being snapped under this bead onthe cup. Likewise such a cap may be snapped'over'the upper edge portionof a glass or tumbler, as

shown in Figure 4, which may likewise be formed ,with a thickened'beadportion about its upper edge, or the cap may be engaged with the upperedge of a cup which flares slig'htlyatits upper end rather than havingany pronounced .bead thereat, both flaring and a slight bead being shownin Figure 4. :If desired the cap may be sealed to the receptacle as byany suitable means such as a strip of cellulose compound shrunkthereover in accordance with well known practice.

and the head 62.

its lower face to permit the entry thereinto of By forming the marginalbead on the cap flange of highly compacted paper stock without fold orseam, it is capable of withstanding very severe service without beingdamaged and thus a very secure sealing of the contents of the cup ortumbler may be readily effected.

The block 28 of the upper die memberis backed up by a spring 60 reactingbetween a plug 6| The plug 6! is recessed in the upper end of a post 63on which the block 28 may slide. This post is provided with a head 64 atits lower end seated in recesses in the segmental portions 2| and 22,which are supported by this head. This head and the ring 260 act assupporting members between which the segmental portions are movable. Thepost 63 is also provided with transverse perforations 65 through whichthe springs 25 pass and it has a collar 66 fixed to its upper end as bythe pin 61 to retain itin' assembled relation to the block the casing12.

28. In the position shown in Figure 1, the collar 66 rests in acounterbored portion 68 in the up:

ber 42, so that this block is held in assembled tion, the lower end ofthe casing 12 defining its upper limit. The parts of the upper diemember which are movable relative to the casing are thus held assembledby the sleeve I4, the spring '60 holding the forming member 42 normallyelevated in the position of Figure 1 when the upper die member iselevated.

From the foregoing description of the cap and its method of formationand mechanism for so forming it, it should be evident that variousmodifications and changes can be made without departing from the spiritor scope of this invention as defined by the appended claims.

I claim:

1. In combination, a pair of cooperating dies, one of said dieshaving asocket and a yielding base for said socket, the other of said dieshaving a plunger adapted to enter said socket and provided withsegmental portions relatively movable to expand and contract and whenexpanded to form an unbroken circumference, said portions 7 having anoutwardly extending rib at their outer ends cooperating with the innerwall of said socket when said plunger is in said socket to hold betweenthem a-marginal flange of a disk formed upby the insertion of saidplunger into said sock: et with said disk therebetween and to form anannular channel above said rib portion wider than the thickness of saidflange, means for expanding said segmental portions when said plungerhas depressed said base, means on said other die entering said channeland engaging the free edge of said flange for molding said free edgeportion between said segmental portions and socket wall into a seamlessbead thicker than the remainder of said flange, and means for retractingsaid segmental portions on release of pressure between said dies to freesaid portions from beneath said flange bead.

2. A die including a casing, an expansible and collapsible sectionincluding a plurality of relatively movable parts, a member mounted formotion transverse to the expanding and collapsing movements of saidparts and cooperating to expand said section on motion of said member inone direction, means yieldingly tending to collapse said section, meanssupporting said parts in operativerelation to saidmember, means holdingsaid member assembled with relation to said casing with capability of.limited axial movement, means yieldingly tending to hold said member atone limit of its motion, and an annular forming member rigidly fixed tosaid casing in position to extend outwardly of said parts when saidmember is at the other limit of its motion;

3. A die including an expansible and collapsible'section, said sectioncomprising a plurality of relatively movable parts which when inexpanded condition present together a continuous surface, said partshaving mating faces inclined to the collapsing direction such that thecollapsing motion of certain of said parts frees others for collapsingmovement, means biasing said section to collapsed condition, meansoperative'to expand said section, and a member forming an outer wallabout said section when said section is expanded, said die includingmeans operatively connecting said member and operative means to retractsaid member axially relative to said permit said section to collapse.

4. A die including a casing, an expansible and collapsible sectionincluding a plurality of relatively movable parts each having an annularrib portion, said rib portions together forming an unbroken annular ribat said section when said parts are expanded, a member mounted formotion transverse to the expanding and collapsing movements of saidparts and cooperating to expand said section on motion of said member inone direction, means yieldlngly tending to collapse said section, meanssupporting said parts in operative relation to said member, meansholding said member assembled with relation to said casing withcapability of limited axial movement, means yieldingly tending to holdsaid member at one limit of its motion, and an annular forming memberrigidly fixed to said casing in position to extend outwardly of saidparts when said member is at the other limit of its motion, and having aforming face cooperating with said rib.

CARL W. GOODWIN.

